Seroprevalence of HTLV-I and HTLV-II among a cohort of HIV-infected women and women at risk for HIV infection

Objectives: To determine the seroprevalence of, and risk factors for, HTLV- I and HTLV-II infection among HIV-infected women and women at high risk for HIV infection. Design: Cross-sectional analysis of baseline data for women enrolled in the prospective Women's Interagency HIV Study (WIHS). Methods: From October 1994 through November 1995, 2657 women from five metr opolitan areas in the United States (Chicago, Los Angeles, New York City [t wo sites], Northern California, and Washington DC) were enrolled in WIHS. A n interview-based survey collected data on demographics, behavior, and medi cal history. HTLV-I and HTLV-II determinations were made using a combined H TLV-I/HTLV-II indirect immunofluorescent antibody (IFA) screening test, an IFA titration specificity test, and individual HTLV-I and HTLV-II confirmat ory Western blots. Fisher's exact tests and logistic regression were used t o determine univariate and multivariate independent predictors for HTLV-II infection. Results: Of 2625 women enrolled in WIHS with confirmed HIV results, 2487 (9 5%) were tested for HTLV-I and HTLV-II. Of these, 241 (10%) were HTLV-II-se ropositive and 13 (0.5%) were HTLV-I-seropositive. On multivariate analysis , independent predictors of HTLV-II infection included injection drug use ( OR = 5.2; p <.001), black race(OR = 3.6; p < 0.001), age >35 years (OR = 3. 3; p <.001) and a history of sex with a male injecting drug user (OR = 1.9; p <.001). Among women infected with HIV, the seroprevalence of HTLV-II was 11% compared with 6% for women at risk for HIV but not infected (p <.001). However, HIV was not an independent predictor of HTLV-II infection in mult ivariate analysis. Conclusions: This cross-sectional analysis confirms that HTLV-II is found c ommonly in HIV-infected women and uninfected women at risk for HIV in major urban areas throughout the United States and that HTLV-II is far more comm on than HTLV-I in these populations. Although injecting drug use is most st rongly associated with HTLV-II infection, sexual transmission likely contri butes to the high HTLV-II seroprevalence in this cohort.